Shareholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
	Nov. 05, 2015	Oct. 30, 2015	Oct. 31, 2014
Shareholders' Equity [Abstract]
Common stock issued resulting from vesting of share-based compensation awards and stock option exercises (in shares)		53,854
Adjustments related to tax withholding and stock issued for share based compensation awards		$ 5,243
Shares of common stock repurchased (in shares)		100,000
Stock repurchase aggregate value		$ 14,653
Share-based compensation expense		1,952
Tax benefit realized upon exercise of share-based compensation awards		$ 1,920
Dividends [Line Items]
Cash dividends paid (in dollars per share)		$ 4.10	$ 1.00
Cash dividends declared (in dollars per share)		1.10	$ 1.00
First Regular Dividends [Member]
Dividends [Line Items]
Cash dividends paid (in dollars per share)		$ 1.10
Second Regular Dividends [Member]
Dividends [Line Items]
Dividend payment date		Nov. 05, 2015
Dividend record date		Oct. 16, 2015
Second Regular Dividends [Member] | Subsequent Event [Member]
Dividends [Line Items]
Cash dividends declared (in dollars per share)	$ 1.10
Special Dividends [Member]
Dividends [Line Items]
Cash dividends paid (in dollars per share)		$ 3.00